Nature-inspired tower proposed in Brisbane's CBD

The establishment of a 71-storey, mixed-use building has been proposed in Brisbane, following the filing of a development application with Brisbane City Council.

The proposed building would be erected at 25 Mary Street and bordered by Margaret Street. The site previously obtained development approval for a 46-storey office tower, designed by BVN. Reworked plans by Koichi Takada Architects have led to a 25-storey height increase, a greater setback distance, modifications to the building's form and a change in use from commercial to mixed-use, predominantly residential.

"The design draws inspiration from nature - the height of the proposal naturally invokes the impression of a tree trunk extending up into the sky, with the recreation levels as 'nests' that are inserted vertically throughout the height of the building," said the architects in a design statement. "The materiality of the building seeks to emphasize this connection by making use of warm timber tones to the slab soffits."

If constructed, the building would comprise one-, two-, three- and four-bedroom apartments, wellness amenities such as a gym, yoga rooms, basketball court and sauna, barbeque area, a lobby, and retail tenancy.

The tower features elevated urban parks that are visible from the street. These curved recreational areas have greenery spilling out from within and cascading down the building's facade, breaking up and softening the hard, robust appearance of a conventional tower.

The building stands on a podium and is set back from the surrounding structures up to the 42nd level, as beyond this point, the skyline remains relatively unobstructed. The building is shaded on every floor with slab projections that provide protection from harsh weather.

Planning documents state the podium design "references the horizontality of the tower above at a more fine-grained scale." A "timber waterfall" feature reveals itself on the podium, with greenery once again cascading down. Green walls are located on both sides of the podium to "soften the edges of the building."

A retail tenancy on the ground level provides street-level activation. The lobby, also located on the ground floor, is a double height volume with a glazed entrance, creating "the opportunity for passive surveillance of the street," plans state.

The design team has integrated passive design strategies to maximize the flow of breeze and optimize natural light within the building through the incorporation of balconies, a primarily glazed facade, postioning of windows and the curved profile of the urban parks, which provide wind breaks for wind to pass through the tower rather than flowing straight up or down the building.

The tower has been design in accordance with Brisbane City Council's Buildings that Breathe design guide. The upper level provides occupants with the ability to adjust and control ventilation intensity on their balconies through "highly engineered" ledge detail. These "breathable" balconies are sheltered and have been inspired by verandahs typically associated with traditional Queenslander houses. Natural ventilation slots have also been integrated into every floor, with wind sensors providing control over operation.

A synagogue that currently exists on the site would be retained.

Planning documents can be viewed on the Brisbane City Council development portal.